As mentioned in the comments, when both search queries that do not work using those URLs are typed in manually on the Google homepage 'I'm Feeling Lucky' does work (note that you will have to disable Google Instant to use the button). However, when I copy the resulting Google URL (captured using Firebug) and paste that in the location bar it still doesn't work. An example full URL is:

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It worked for me when I copied the search terms into a new search and clicked "I'm Feeling Lucky".
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amiregelzAug 11 '12 at 12:01

@amiregelz interestingly enough that works for me as well, however when I copy the resulting Google URL (captured using Firebug) and paste that in the location bar it doesn't work.
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Bruce van der KooijAug 11 '12 at 17:54